摘要 |
At least one column of a latch array includes a tri-state buffer in the upper portion of the column that receives the output of the uppermost group of latches of the column as its input, and which is enabled by a dump signal when a latch in the upper portion is addressed. When the dump signal that triggers the tri-state buffer is active, whatever is at the input of the tri-state buffer is driven by the buffer to the bottom of the latch array column, thereby providing the driven signal with sufficient strength to obviate transition timing and signal integrity problems. When the dump signal that triggers the tri-state buffer is not asserted, the tri-state buffer output exhibits high impedance, which isolates the lower portion of the latch array column from the upper portion of the latch array column, thereby preventing the capacitance associated with the line connecting the tri-state buffer to the output of the uppermost latch from affecting the driving ability of the latches in the lower portion of the column.
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